Catheter Directed Thrombolysis
When blood does not flow smoothly through a vessel, it can begin to coagulate, turning from a free-flowing liquid to a semi-solid gel, or blood clots.
A blood clot, or thrombus, that forms within a blood vessel may continue to grow, blocking off the blood supply to certain parts of the body and causing damage to tissues and organs. In some patients, blood clots come from one site, dislodge, travel downstream, and lodge in relatively small vessels causing a blockage, or embolization. Untreated, a vascular blockage due to thrombosis or embolization, can result in the loss of an organ or extremity, with potentially life-threatening consequences.
Catheter-directed thrombolysis is a minimally invasive treatment that dissolves abnormal blood clots in blood vessels to help improve blood flow and prevent damage to tissues and organs.
A catheter is inserted into a vein in the leg and carefully threaded through the vein with the help of x-ray imaging until it reaches the site of the blood clot.
When the tip of the catheter reaches the clot, a clot-dissolving drug is infused into the clot through the catheter. In most cases, the blood clot will completely dissolve within one to two days. The procedure is monitored using special x-rays and ultrasound scans. These images will also help determine if the vein wall is narrowed or damaged, making it prone to more clots in the future. If this type of damage has occurred, an additional procedure may be needed, such as a balloon angioplasty or placing a small mesh stent into the vein to keep it from clotting again.
What are some common uses of the procedure?
Catheter-directed thrombolysis is used to treat blood clots in arteries and veins resulting from any of these causes:
- Thrombosis in the vascular bed of the diseased arteries, such as thrombosis in an arm or leg artery that has severe narrowing due to atherosclerosis.
- deep vein thrombosis, a condition in which a blood clot forms in a main vein that returns blood flow from the arms or legs back to the heart and lungs. This type of clot may grow big enough to completely block the vein, posing serious risk if part of it breaks off and travels to the lungs (called pulmonary embolism).
- Slowed circulation caused by heart disease, which can allow a blood clot to form in one of the heart’s chambers. A clot that breaks loose, travels through the bloodstream and lodges in either an organ or artery forming a complete blockage in blood flow at that point is called an embolism.
- Thrombosis of the dialysis fistulas or grafts.
- Pulmonary embolism.
- Thrombosis of the portal vein and other mesenteric veins.
How should I prepare?
Prior to your procedure, your blood may be tested to determine how well your kidneys are functioning and whether your blood clots normally.
You should report to your doctor all medications that you are taking, including herbal supplements, and if you have any allergies, especially to local anesthetic medications, general anesthesia or to contrast materials containing iodine (sometimes referred to as “dye” or “x-ray dye”). Your physician may advise you to stop taking aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs) or blood thinners for a specified period of time before your procedure.
Also inform your doctor about recent illnesses or other medical conditions.
Women should always inform their physician and x-ray technologist if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to radiation. If an x-ray is necessary, precautions will be taken to minimize radiation exposure to the baby. See the Safety page for more information about pregnancy and x-rays.
You will receive specific instructions on how to prepare, including any changes that need to be made to your regular medication schedule.
You will be admitted to the hospital on the morning of your procedure and be assessed by the interventional radiologist before the procedure begins.
Dialysis fistula or graft thrombolysis patients are generally discharged the same day; however, most other conditions require hospitalization for several days with careful monitoring.
You will be given a gown to wear during the procedure.
What Are the Benefits/Risks of Catheter-Directed Thrombolysis?
- Catheter-directed thrombolysis can greatly improve blood flow and reduce or eliminate the related symptoms and effects without the need for more invasive surgery.
- Thrombolysis is a safe, highly effective way of re-establishing circulation blocked by a clot.
- Thrombolysis is less invasive than conventional open surgery to remove clots and the hospital stay is relatively brief. Blood loss is less than with traditional surgical treatment and there is no obvious surgical incision.
- No surgical incision is needed—only a small nick in the skin that does not have to be stitched closed.
- Any procedure where the skin is penetrated carries a risk of infection. The chance of infection requiring antibiotic treatment appears to be less than one in 1,000.
- There is a very slight risk of an allergic reaction if contrast material is injected.
- Any procedure that involves placement of a catheter inside a blood vessel carries certain risks. These risks include damage to the blood vessel, bruising or bleeding at the puncture site, and infection.
- There is a risk of infection after thrombolysis.
- Whenever anticoagulant or thrombolytic agents are used, there is a risk that bleeding will occur elsewhere in the body. The most serious complication is intracranial bleeding, or bleeding in the brain.
- In some cases the material that is blocking your vessel may move to another part of the vascular system. Usually this can be treated with further thrombolysis but sometimes may require surgery.
- There is a risk of kidney damage especially in patients with pre-existing kidney disease.